Pole-piece for dynamo-electric machines.



L. E. UNDEPNVOGDx POLE PIECE ECB DYNAMC ELECTRIC MACHINES.

- APPLIUATION FILED JAN.11, 1908. 920,886. Patented May 4, 1909. 2 SHEETS-SHEET 2.

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Wtzsses: Inventor- Lous Bunderwood,

Uivrrn sfriirns riirn NT GFFCFL LOUIS lil. UNDERWOOD, Ul" LYNN, MASSACHUSETTS. iSSibQli TU (fCNl'lRfil. ELEVTRU" (T011- PANY, .i CORPORATION or QLE-PECE FOR DYNAMIC-ELECTRIC MACZHNES No. encens Specieation of Letters Patent.

Patented May 4, 1909 Applizelion filed January 11, 1968. Serial No. 416,380.

1o all whom it lnun; concern.

Be it known that' Lofs E. Unnnsvvoon, a citizen of the tetes, residing at Lynn, county ci? lisses, te oi Massachusetts, have vinvented certein new and useful .lniproveinents in idole-Pieces for Dynamo- Electric Machines, oi which the following is e specification.

My present invention relates to dynamo'- electric machines, and more perticulrirlyto the consti'i'iction of pole pieces therefor, and lies for its object an improved construction whereby such machines are chenpened.

My invention enables me to lasten pole tips on the oles of dynamo-electric machines in :i very c esp and .satisfactory manner.v It consists inv fastening laminated tips having proecting end plates to ole pieces cast integm with the frame of t e machine, the cast portions of the pole being bored out to a diaineter somewhat greeter than the diameter of the armature of the dynamo-electric ina;- chine. The fastening means for the tips engage the end 1plates and the cast portions of the ole.

y Mly vention is particularly advantageous when a plied to coinniutating pel-es, especially w en' such poles are very Anarrow inaking it difficult to use bolts for fastening the tipsin place. l

For a better understanding of my invention and the advantages 'possessed by it, reference maybe had to the following description taken in connection With the accompanying drawing in which* Figure l is a side view of a dynamo-electric machine embodying my' invention, with parts broken away and in section to show the interior construction; Fig'. 2 is an endvieiv of the machine of Fig. 1, with'pa-rts broken I away and in section; Fig. 3 is an enlarged sec- -than the punchings tating poles 13, ere cast integral with the frame to the circumference 14 which is somewhat greater than the outside diameter' of the armature 7. These surfaces of the poles are bored so as to give a iiiiished surface, at the-saine time es the surfaces 15 and 16 of the freine. The mein field coils 17 when placed in position may be held there by the main pole tips 18. These pole tips are fastened iii place' by bolts 19. The pole tips 20 of the coininutiiting poles have end punchings 21 which may be considerably thicker 2.' which go to make up the pole tips. ln each of the pole tips these end punchiiigs project a considerable distance toward the baise of the pole, and a rivet 23 holds all of the puncliiiigs together. Through the projecting portions of the end punchings holes are nia de, and a corresponding hole 2-l is drilled through the pole core 13, but at a slightly greater distance fromthc bored surface thanthe holes punched in the end plates. T Wo pins 25, which are partly tapered at their ends 26, :ire driven in the hole 2l, one from each side. ln this waythe the pole tip iirnily into its seat. When the pins are driven home the field coil 27 maybe slipped on. When the pole tip has thus been placed in position it is unnecessary4 thereafter to remove the same. The coil 27' is held in position by means of a pin 28 which passes through a hole 29 in the pole tip.

l have chosen to illustrate my invention in connection with a coininutating pole, but it is evident to those skilled in the art that this construction may also be used with main poles. that my invention is not limited to the particular construction shown and described,

and l nim in the appended claims to cover tion of my improved pole piece; and Fig. -l is iin end viev; of the saine.

the machine to which the end members 2 and 3 are fastened by means of bolts. These end Further, l desire it to be understood' Vrelative positions of the holes tend to'draiv all modifications which do not depart from i the spirit of my invention. Referring to the drawings, 1 is the frame ot 1 Vi'hat l claim as new and desire to -secure by Letters Patent of the Liiited States, is,* 1. In combination with the armature of a dynziiiio-clectric machine, a. field magnet and are fastened to studs 10, which are suiti ably supported by moans of a yoke 11 but are insulated therefrom in any suitable manner.

The main poles 12, as Well as the commufri-.nie having parts oi the pole pieces cast integral with said frame und bored out to il diameter greater than the diameter oll said urmature/laminated pole tips hiivingend vplates of greater length thun the other ylamiine, und means engaging said end plates :ind said cast portions gor holding said pole -tips in place.

'2. 1n e dynemo-eeetre machine, a pele pleee eensxstmg-of part Gesu mtegral wlth the frame of the machine havin a bored v f g suffeee end a hole therein, and a part built f up 0i ienne.etlens, 'che end lemuue of whlch paogeet o'zfe sem east portlon ef the pele E pleee and' have hoes therein, seid hole in the east portlen beleg et e greete dlstanee 'trom the bored surface than the hoes m the end Q emme, and pins passing through said bales 1D whereby seid laminated pertion of the pele is (hewn firmly' against Seid bored surface.

1n Wness Wheleof, I have hereunto set my hand this 6th lay ei' January, 1908.

Witnesses:

ALEX. F. MACDONALD, JOHN A. MCMANUS, Jr. 

